Gas turbine engines are used to power aircraft, watercraft, power generators, and the like. Gas turbine engines generally include compressor wheels and turbine wheels coupled to shafts to form rotors that are supported in cases for rotation within the cases. The rotors are typically mounted on bearings that allow rotation relative to the cases. Most bearings perform best in a lubricated environment in which a lubricant reduces friction between components during rotation of the rotor.
Many gas turbine engines include lubrication systems that circulate lubricants throughout the engine. These lubrication systems may clean, cool, and distribute lubricants, such as oil, to bearings and other parts of the engine. To properly circulate lubricants through an engine, some lubrication systems control the air between lubricated cavities to encourage desired movement of the lubricant through the system.